Make sure SDL_Init() was called before SDL_VideoInfo()

by adding GLimp_PreInit()

neo/renderer/RenderSystem_init.cpp

@@ -870,6 +870,10 @@ void R_InitOpenGL()
 		common->FatalError( "R_InitOpenGL called while active" );
 	}
 	
+	// DG: make sure SDL has setup video so getting supported modes in R_SetNewMode() works
+	GLimp_PreInit();
+	// DG end
+
 	R_SetNewMode( true );
 	
 	

neo/renderer/tr_local.h

@@ -1052,6 +1052,10 @@ struct glimpParms_t
 	int			multiSamples;
 };
 
+// DG: R_GetModeListForDisplay is called before GLimp_Init(), but SDL needs SDL_Init() first.
+// So add PreInit for platforms that need it, others can just stub it.
+void		GLimp_PreInit();
+
 bool		GLimp_Init( glimpParms_t parms );
 // If the desired mode can't be set satisfactorily, false will be returned.
 // If succesful, sets glConfig.nativeScreenWidth, glConfig.nativeScreenHeight, and glConfig.pixelAspect

neo/sys/sdl/sdl_glimp.cpp

@@ -53,6 +53,25 @@ static SDL_Surface* window = NULL;
 bool QGL_Init( const char* dllname );
 void QGL_Shutdown();
 
+/*
+===================
+GLimp_PreInit
+
+ R_GetModeListForDisplay is called before GLimp_Init(), but SDL needs SDL_Init() first.
+ So do that in GLimp_PreInit()
+ Calling that function more than once doesn't make a difference
+===================
+*/
+void GLimp_PreInit() // DG: added this function for SDL compatibility
+{
+	if( !SDL_WasInit( SDL_INIT_VIDEO ) )
+	{
+		if( SDL_Init( SDL_INIT_VIDEO ) )
+			common->Error( "Error while initializing SDL: %s", SDL_GetError() );
+	}
+}
+
+
 /*
 ===================
 GLimp_Init
@@ -62,11 +81,7 @@ bool GLimp_Init( glimpParms_t parms )
 {
 	common->Printf( "Initializing OpenGL subsystem\n" );
 	
-	if( !SDL_WasInit( SDL_INIT_VIDEO ) )
+	GLimp_PreInit(); // DG: make sure SDL is initialized
-	{
-		if( SDL_Init( SDL_INIT_VIDEO ) )
-			common->Error( "Error while initializing SDL: %s", SDL_GetError() );
-	}
 	
 	Uint32 flags = SDL_WINDOW_OPENGL;
 	
@@ -378,6 +393,11 @@ bool R_GetModeListForDisplay( const int requestedDisplayNum, idList<vidMode_t>&
 	bool	verbose = false;
 
 	const SDL_VideoInfo* videoInfo = SDL_GetVideoInfo();
+	if( videoInfo == NULL )
+	{
+		// DG: yes, this can actually fail, e.g. if SDL_Init( SDL_INIT_VIDEO ) wasn't called
+		common->Error( "Can't get Video Info!\n" );
+	}
 	
 	SDL_Rect** modes = SDL_ListModes( videoInfo->vfmt, SDL_OPENGL | SDL_FULLSCREEN );
 	

neo/sys/win32/win_glimp.cpp

@@ -1253,6 +1253,10 @@ static bool GLW_ChangeDislaySettingsIfNeeded( glimpParms_t parms )
 	return false;
 }
 
+void GLimp_PreInit() {
+	// DG: not needed on this platform, so just do nothing
+}
+
 /*
 ===================
 GLimp_Init